Ultrasonic characterization of microstructure in powder metal alloy

B. R. Tittmann, M. Abdel-Gawad, K. Fertig

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

The ultrasonic wave propagation characteristics were measured for IN-100, a powder metallurgy alloy used for aircraft engine components. This material was selected as a model system for testing the feasibility of characterizing the microstructure of a variety of inhomogeneous media including powder metals, ceramics, castings, and composites. The data were obtained for a frequency range from about 2-20 MHz and were statistically averaged over numerous volume elements of the samples. Micrographical examination provided size and number distributions for grain and pore structure. The results showed that the predominant source for the ultrasonic attenuation and backscatter was a dense (∼100/mm3) distribution of small micropores (∼10 μm radius). Two samples with different micropore densities were studied in detail to test the feasibility of calculating from observed microstructural parameters the frequency dependence of the microstructural backscatter in the regime for which the wavelength is much larger than the size of the individual scattering centers. Excellent agreement was found between predicted and observed values so as to demonstrate the feasibility of solving the forward problem. The results suggest a way towards the nondestructive detection and characterization of anomalous distributions of micropores when conventional ultrasonics imaging is difficult. The findings are potentially significant toward the application of the early detection of porosity during the materials fabrication process and after manufacturing of potential sites for stress-induced void coalescence leading to crack initiation and subsequent failure.

Original languageEnglish (US)
Pages (from-to)119-133
Number of pages15
JournalResearch in Nondestructive Evaluation
Volume2
Issue number2
DOIs
StatePublished - Jun 1 1990

Fingerprint

metal powder
Powder metals
ultrasonics
Ultrasonics
Ultrasonic propagation
Ultrasonic imaging
microstructure
Microstructure
Aircraft engines
Cermets
Crystal microstructure
Powder metallurgy
Pore structure
Coalescence
Crack initiation
porosity
aircraft engines
powder metallurgy
Porosity
crack initiation

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Tittmann, B. R. ; Abdel-Gawad, M. ; Fertig, K. / Ultrasonic characterization of microstructure in powder metal alloy. In: Research in Nondestructive Evaluation. 1990 ; Vol. 2, No. 2. pp. 119-133.
@article{bab309ab0e794ed096e61a82368593c1,
title = "Ultrasonic characterization of microstructure in powder metal alloy",
abstract = "The ultrasonic wave propagation characteristics were measured for IN-100, a powder metallurgy alloy used for aircraft engine components. This material was selected as a model system for testing the feasibility of characterizing the microstructure of a variety of inhomogeneous media including powder metals, ceramics, castings, and composites. The data were obtained for a frequency range from about 2-20 MHz and were statistically averaged over numerous volume elements of the samples. Micrographical examination provided size and number distributions for grain and pore structure. The results showed that the predominant source for the ultrasonic attenuation and backscatter was a dense (∼100/mm3) distribution of small micropores (∼10 μm radius). Two samples with different micropore densities were studied in detail to test the feasibility of calculating from observed microstructural parameters the frequency dependence of the microstructural backscatter in the regime for which the wavelength is much larger than the size of the individual scattering centers. Excellent agreement was found between predicted and observed values so as to demonstrate the feasibility of solving the forward problem. The results suggest a way towards the nondestructive detection and characterization of anomalous distributions of micropores when conventional ultrasonics imaging is difficult. The findings are potentially significant toward the application of the early detection of porosity during the materials fabrication process and after manufacturing of potential sites for stress-induced void coalescence leading to crack initiation and subsequent failure.",
author = "Tittmann, {B. R.} and M. Abdel-Gawad and K. Fertig",
year = "1990",
month = "6",
day = "1",
doi = "10.1007/BF01606424",
language = "English (US)",
volume = "2",
pages = "119--133",
journal = "Research in Nondestructive Evaluation",
issn = "0934-9847",
publisher = "Taylor and Francis Ltd.",
number = "2",

}

Ultrasonic characterization of microstructure in powder metal alloy. / Tittmann, B. R.; Abdel-Gawad, M.; Fertig, K.

In: Research in Nondestructive Evaluation, Vol. 2, No. 2, 01.06.1990, p. 119-133.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Ultrasonic characterization of microstructure in powder metal alloy

AU - Tittmann, B. R.

AU - Abdel-Gawad, M.

AU - Fertig, K.

PY - 1990/6/1

Y1 - 1990/6/1

N2 - The ultrasonic wave propagation characteristics were measured for IN-100, a powder metallurgy alloy used for aircraft engine components. This material was selected as a model system for testing the feasibility of characterizing the microstructure of a variety of inhomogeneous media including powder metals, ceramics, castings, and composites. The data were obtained for a frequency range from about 2-20 MHz and were statistically averaged over numerous volume elements of the samples. Micrographical examination provided size and number distributions for grain and pore structure. The results showed that the predominant source for the ultrasonic attenuation and backscatter was a dense (∼100/mm3) distribution of small micropores (∼10 μm radius). Two samples with different micropore densities were studied in detail to test the feasibility of calculating from observed microstructural parameters the frequency dependence of the microstructural backscatter in the regime for which the wavelength is much larger than the size of the individual scattering centers. Excellent agreement was found between predicted and observed values so as to demonstrate the feasibility of solving the forward problem. The results suggest a way towards the nondestructive detection and characterization of anomalous distributions of micropores when conventional ultrasonics imaging is difficult. The findings are potentially significant toward the application of the early detection of porosity during the materials fabrication process and after manufacturing of potential sites for stress-induced void coalescence leading to crack initiation and subsequent failure.

AB - The ultrasonic wave propagation characteristics were measured for IN-100, a powder metallurgy alloy used for aircraft engine components. This material was selected as a model system for testing the feasibility of characterizing the microstructure of a variety of inhomogeneous media including powder metals, ceramics, castings, and composites. The data were obtained for a frequency range from about 2-20 MHz and were statistically averaged over numerous volume elements of the samples. Micrographical examination provided size and number distributions for grain and pore structure. The results showed that the predominant source for the ultrasonic attenuation and backscatter was a dense (∼100/mm3) distribution of small micropores (∼10 μm radius). Two samples with different micropore densities were studied in detail to test the feasibility of calculating from observed microstructural parameters the frequency dependence of the microstructural backscatter in the regime for which the wavelength is much larger than the size of the individual scattering centers. Excellent agreement was found between predicted and observed values so as to demonstrate the feasibility of solving the forward problem. The results suggest a way towards the nondestructive detection and characterization of anomalous distributions of micropores when conventional ultrasonics imaging is difficult. The findings are potentially significant toward the application of the early detection of porosity during the materials fabrication process and after manufacturing of potential sites for stress-induced void coalescence leading to crack initiation and subsequent failure.

UR - http://www.scopus.com/inward/record.url?scp=1342318525&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=1342318525&partnerID=8YFLogxK

U2 - 10.1007/BF01606424

DO - 10.1007/BF01606424

M3 - Article

AN - SCOPUS:1342318525

VL - 2

SP - 119

EP - 133

JO - Research in Nondestructive Evaluation

JF - Research in Nondestructive Evaluation

SN - 0934-9847

IS - 2

ER -